RDMA/uverbs: Optimize clearing of extra bytes in response

Clear extra bytes in response in batch manner instead
of doing it per-byte.

Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Yuval Shaia <yuval.shaia@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
This commit is contained in:
Leon Romanovsky 2018-12-11 11:41:05 +02:00 committed by Jason Gunthorpe
parent a276a4d93b
commit 9435ef4cae
1 changed files with 8 additions and 6 deletions

View File

@ -58,19 +58,21 @@
static int uverbs_response(struct uverbs_attr_bundle *attrs, const void *resp,
size_t resp_len)
{
u8 __user *cur = attrs->ucore.outbuf + resp_len;
u8 __user *end = attrs->ucore.outbuf + attrs->ucore.outlen;
int ret;
if (copy_to_user(attrs->ucore.outbuf, resp,
min(attrs->ucore.outlen, resp_len)))
return -EFAULT;
/* Zero fill any extra memory that user space might have provided */
for (; cur < end; cur++) {
ret = put_user(0, cur);
if (resp_len < attrs->ucore.outlen) {
/*
* Zero fill any extra memory that user
* space might have provided.
*/
ret = clear_user(attrs->ucore.outbuf + resp_len,
attrs->ucore.outlen - resp_len);
if (ret)
return ret;
return -EFAULT;
}
return 0;